Drug makers Eli Lilly, Bayer, Amylin and Cephalon have all been cited by the U.S. Food & Drug Administration (FDA) for misleading drug promotions. The promotions that have attracted the FDA’s scrutiny involve Eli Lilly’s antidepressant Cymbalta, Cephalon’s Treanda, a lymphoma treatment, the diabetes drug Byetta, which is marketed jointly by Amylin and Eli Lilly, and Bayer’s birth control implant Mirena.

The FDA regularly issues letters to companies that do not follow regulations for manufacturing and marketing. The four letters were issued on separate dates between mid-December and early January.

In a warning letter to Eli Lilly, the FDA said claims appearing a in print ad and the WebMD LLC Little Blue Book regarding Cymbalta do not adequately display information about the drug’s side effects. The FDA also said it was not aware of clinical data supporting pain reduction claims made in the ad appearing in the WebMD Little Blue Book. Cymbalta is approved to treat depression, generalized anxiety disorder, diabetic nerve pain and the pain ailment fibromyalgia. Cymbalta’s side effects include hepatotoxicity, or liver damage, abnormal bleeding and nausea.

The warning letter for Treanda, which has been associated with side effects including serious infections and skin reactions, said a pocket dosing card for the drug was “false or misleading because it omits important risk information.” Cephalon was told to stop disseminating the Treanda dosing card.

The Byetta letter cited statements made by an Eli Lilly representative at the 91st Endocrine Society annual meeting in Washington, D.C. According to the letter, the rep told an FDA official that Byetta had cardiovascular benefits because of a positive effect on cholesterol and triglyceride levels. The agency said it was not aware of any data to support such a claim. The Eli Lilly representative also said Byetta could be used on its own, although the FDA had not yet approved it for independent use. The Byetta letter also said Amylin and Eli Lilly exaggerated the drug’s ability to help patients lose weight.

Bayer was cited for a Mirena ad that suggests use of the device increased levels of romance and emotional satisfaction. The FDA said it “not aware of any evidence that suggests that women using Mirena for birth control experience an increase in reconnection, romance or intimacy with their partners.” The agency also said that a script it reviewed for a live program on Mirena doesn’t adequately convey that if a woman becomes pregnant while on the medicine she may lose her baby.